1. Field of the Invention
The present invention relates to electrical current generation from nuclear fusion. More particularly, the invention concerns improvements in a Helium-3 (3He) fusion device, and particularly a (3He—3He) fusion device with electrostatic reaction confinement.
2. Description of Prior Art
By the year 2050 AD, the Earth may have run out of all economically recoverable fossil fuels, such as oil and natural gas. There should still be plenty of coal, but only if mankind is willing to put up with its associated greenhouse gasses. Also, there may be no place to put the toxic residues of present nuclear fission reactors. West Valley N.Y. doesn't want them and neither does Nevada. Worse yet, in 2050 AD all the alternate sources of energy, like hydroelectric, wind, wood, tidal, geothermal and solar, will not supply even 25% of the energy mankind will need to feed the 10 billion people that will populate Earth by that time.
Present day nuclear fission reactors operate like a slow atomic (“A”) bomb, splitting heavy plutonium or uranium atoms into smaller elements and giving off power. American and Russian nuclear engineers and physicists have succeeded in slowing down the fission reaction to produce useful power, as exemplified by Three-Mile Island and Chernobyl, (a mixed blessing!). Others have accomplished this more successfully. France generates a significant part of its energy requirements from fission reactors and has achieved a perfect safety record. Their reactors are all of the same design and are run by nuclear engineers. In the U.S., the reactors are built differently and their operation is left mostly to technicians. But France still has the same problem that the U.S. has in regard to the disposal of the toxic residues.
Mankind may have no alternative but to develop the ability to harness useful energy from nuclear fusion. To date, however, it has not been feasible to produce a controlled, sustainable nuclear fusion reaction, at least not to the point of producing useful power. Nuclear fusion devices must operate like a slow hydrogen (“H”) bomb, fusing light weight atoms such as hydrogen or helium.
Present nuclear fusion devices are classified by the methods used to support the nuclear fusion reaction, which takes place at a temperature much hotter than the surface of the Sun. No container on Earth can hold it. The reaction must therefore be suspended by either electromagnetic, gravitational (inertial) or electrostatic fields.
A fusion device known as the “TOKAMAK” at Princeton, N.J. operates by magnetic confinement in a huge 250 ton supercooled electromagnet. The electromagnet exquisitely controls and shapes a magnetic field, which physically supports the reaction. As far as known, the TOKAMAK device has never operated longer than a few seconds at a time and the federal government has withdrawn its support.
With inertial confinement, hundreds of powerful lasers are pointed concentrically at a gold capsule containing a small amount of hydrogen. The pressure and the temperature of the capsule are raised to fusion levels and produce a burst of energy. This process must then be repeated, perhaps 100 times per second, to provide a reasonably continuous flow of power. Two such devices exist in the USA, one in Rochester, N.Y. and one in Livermore, Calif. As far as known, neither has ever approached “break-even” in power generation.
U.S. Pat. No. 4,826,646 of Bussard, the contents of which are incorporated herein by this reference, discloses a fusion device using electrostatic confinement of the reaction. The fusion reaction is confined by electrostatic forces in a large potential well within a vacuum chamber. The potential well is created by confining electrons using a quasi-spherical-cusp magnetic field to form a highly negatively charged virtual anode. Positive ions, such as Deuterium (D), Tritium (T), and/or 3He are introduced into the vacuum chamber and pulled into the well, where they have an opportunity to fuse according to fusion reactions involving D-T, D-D, and D-3He.
Dr. Gerald Kulcinski and co-investigators at the Fusion Technology Institute at the University of Wisconsin/Madison are seeking to demonstrate nuclear fusion energy using inertial electrostatic confinement (IEC) and combinations of 3He and D ion starting materials. The fusion reaction is confined in a 1000 pound cylindrical aluminum vacuum chamber. This chamber has an inner diameter of 91 cm and an inner height of 65 cm. It contains a pair of concentric, tungsten alloy spherical grids with a very strong electrostatic field inside them. The outer grid is 45 cm in diameter and is grounded. The inner grid is 10 cm in diameter and is connected to a large negative potential via a ceramic insulated electrode that feeds through a small opening in the vacuum chamber. When positive ions (e.g., 3He or D ions) are introduced into the vacuum chamber, they fall into the potential well created by the electrostatic field within the grids and oscillate backwards and forward at increasing speed until two ions collide, fusing into a 4He ion and releasing high energy protons.
This device has been used to successfully demonstrate D-3He and D-D fusion with significant high-velocity proton generation at 40 kV acceleration voltages across the two grids. Although these are significant achievements, no provision has been made to recover useful energy from the device in excess of the input power required to sustain the reactions. Moreover, as far as known, the foregoing device has produced no successful reaction based on the fusion of two 3He ions into one 4He ion with the release of a stream of high velocity protons in the 1 to 10 MeV range. To achieve 3He—3He fusion will require a 200 kV grid voltage. However, the investigators at the Fusion Technology Institute have not been able to use voltages over 80 kV because of arcing between the ceramic insulated electrode and the vacuum chamber. A fusion reaction using 3He alone would be desirable because the fuel (He-3) is non-radioactive, the process is non-radioactive, and the residue (He-4) is non-radioactive. In fact, the residue, He-4, is used to inflate childrens' balloons. Thus, He-3 may be the perfect fuel for fusion-based nuclear reactions. On the other hand, the D-3He and D-D fusion reaction generates a steady stream of neutrons, protons, electrons, helium-4 (He-4), tritium, gamma and x-rays.
Accordingly, improvements are indicated in the construction and implementation of fusion devices.